The present invention relates to an ophthalmologic characteristic measuring apparatus for precisely measuring optical characteristics of the eye to be examined and allowing the examiner to readily understand how an optotype is seen by the eye.
There is conventionally proposed an apparatus configured in such a manner that a subjective optometry device is used for the subject to look at an optotype via a correction lens provided according to the eyesight of the subject, and a point image intensity distribution corresponding to optical characteristics of the eye is measured by using the correction lens system, so that an index image that is actually observed by the eye is calculated from the measured point image intensity distribution and the index image is displayed.
With this apparatus, the examiner observes the index image obtained by arithmetic, and changes one correction lens for another to bring the index image into an optimally focused state, so that the refractive power of the eye can be determined from the amount of correction when the optimum correction lens selected by the examiner is used. Thus, the apparatus has an advantage of eliminating errors in response from the subject, thereby making it possible to perform accurate eye examination.
With this conventional apparatus, however, the examiner needs to perform correction by using correction lenses while observing an index image displayed by arithmetic. This not only results in difficulty in the operation for eye examination, which is a burden on the examiner, but also will cause a pain and a burden to the subject because it takes time for the eye to be examined.
An object of the present invention is to solve this problem of the conventional technique. Another object of the present invention is to provide an ophthalmologic characteristic measuring apparatus that makes it possible to readily observe in a single measurement an image seen by the subject when the subject wears an appropriate correction lens, and therefore perform accurate eye examination in a short time.